I adjust my oil to the life of the engine. I've used 20W-50 for years on many vehicles. Currently I have a 97 OHV with 125K and use 10W-40. With that oil, the oil pressure when hot is about 40# driving and 20# at idle in gear. The same engine with 20W-50 runs around 47# highway and 25# at idle. At startup, the pressure relief valve keeps the pressure at 60#. I see nothing wrong with the pressures of a 10W40 and would sure like to hear pressures from someone who is running 5W-20. Why do you think they have idiot gauges. People would be screaming at their dealers when they saw the wild swings. All my cars go well over 200K.